A fiber strip feeder provided with a feed duct between the entrance rolls and the calendering rolls of a drafting unit of a spinning preparation machine is known having a tangential housing air duct opening into a cylindrical fiber strip feed duct. The "fiber strip" can be a roving or sliver.
Such a device has been described in German Open Application DE-OS No. 30 34 812.
The fiber strip feed duct between the entrance rolls and the calendering rolls of a drafting unit is used as an injector for feeding the roving or sliver between the calendering rolls.
The housing air duct opening into it is inclined tangentially to the fiber strip feed duct so that a fiber strip not only is given a feed motion but also a rotational motion.
The use of a cylindrical fiber strip feed duct is presumed for proper functioning of this apparatus.
It is also known to associate the calendering rolls with a narrow fiber strip funnel to keep the fiber strips strongly compressed and thus to attain a high can filling rate. This known fiber strip funnel however tends to restrict the fiber strip feed and may cause clogging.